Messages in this thread | | | From | "Luck, Tony" <> | Subject | RE: Fwd: PROBLEM: Random kernel panic & system freeze when watching video | Date | Thu, 3 Jan 2013 00:05:28 +0000 |
| |
>I had to build the latest mcelog from kernel.org and it tells you a >little bit more: it is an internal parity error. I don't know, though, >what errors reported in bank 2 pertain to on this cpu model - Intel >should know :).
Intel is a big place ... we didn't document which bank reports which structure in the public data sheet ... so I'd have to find some internal docs for that. Not sure it would help though as the MC2STATUS register value 0xb200000000000005 just says "internal error" - without any extra bits in the "mscod" subfield. This is the "default:" at the end of the internal "switch" where all the usual suspects have been eliminated and we just know that something went wrong.
One possibility is a thermal problem (since I presume that video decode is making the CPU work hard). Does the machine get noticeably warmer, or does the fan kick up to high speed when this happens?
Another (harder to isolate) is power supply ... if the CPU is drawing more power during video decode, then you might see a brownout where voltage drops too low. This could cause all sorts of internal problems.
How predictable is the problem? If you power on the system from cold (unused for a few minutes) and immediately start watching a video (same video in multiple tests) ... do you see the hang/crash at the same point in the movie? Or are there large variations.
If we have a plain s/w bug doing something evil that trips the problem, I'd expect a high level of repeatability. If you have a thermal problem then you may be able to accelerate it by partially blocking the fan exhaust. Electrical ... I suppose it might be different on AC power vs. battery.
-Tony
| |